On Sun, Nov 12, 2017 at 9:18 AM, Thomas Munro <thomas.mu...@enterprisedb.com> wrote: > On Sat, Oct 21, 2017 at 8:09 AM, Robert Haas <robertmh...@gmail.com> wrote: >> On Tue, Oct 17, 2017 at 7:27 AM, Thomas Munro >> <thomas.mu...@enterprisedb.com> wrote: >> >> I don't think overloading force_parallel_mode is a good idea, but >> having some other GUC for this seems OK to me. Not sure I like >> multiplex_gather, though. > > How about parallel_leader_participation = on|off? The attached > version has it that way, and adds regression tests to exercise on, off > and off-but-couldn't-start-any-workers for both kinds of gather node. > > I'm not sure why node->need_to_rescan is initialised by both > ExecGatherInit() and ExecGather(). Only the latter's value matters, > right? >
I don't see anything like need_to_rescan in the GatherState node. Do you intend to say need_to_scan_locally? If yes, then I think whatever you said is right. > I've added this to the January Commitfest. > +1 to this idea. Do you think such an option at table level can be meaningful? We have a parallel_workers as a storage option for tables, so users might want leader to participate in parallelism only for some of the tables. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers